More Predictable, Less Cooperative: The Effects of Personality Disclosure in Strategic Interaction[Plus prévisible, moins coopératif : les effets de la divulgation des traits de personnalité dans l’interaction stratégique]

This study investigates how the disclosure of personality traits affects strategic behaviour in trustsensitive environments. Specifically, we examine whether making information about personality traits visible-either about oneself, one's counterpart, or both-modifies coordination outcomes. In a repeated stag-hunt game, 192 participants were classified as either trusting or mistrusting types and randomly assigned to one of four information conditions (no information, private, public, or full visibility). We elicited first and second-order beliefs across 48 rounds to analyse how trait visibility shapes expectations and behaviour through four mechanisms: (1) self-identification, (2) preferencebased discrimination, (3) first-order belief bias, and (4) second-order belief pessimism. Our resultsshow that when traits are not disclosed, personality has no behavioural effect: trusting and mistrusting types look alike. Once labels appear, behaviour is driven by expectations, not by self-identification or type-based preferences. We observe that labels shift beliefs toward trusting counterparts, but this fades with feedback. Moreover, information increases predictability and strategic alignment, yet can nudge play toward the safer, inefficient equilibrium-so coordination rises even as cooperation can fall.